Fosamax Safety Issues And Dosage

Osteoporosis is a bone-weakening condition that affects more than 8 million women in the U.S. each year and causes more than 1.5 million serious spine, hip, and wrist fractures. These fractures are serious in themselves, and are, in fact, a frequent cause of death and long-term disability in older women. Treating and preventing this serious condition gives patients many years of quality life. The drug Fosamax has been a leading therapy for this condition since it was approved for use by the FDA in 1995.

Preventing the bone loss that leads to these fractures eliminates a serious cause of death and disabling injuries and prevents long and painful recovery times.

Reports of possible side effects from Fosamax and the generic version, Alendronate, have raised questions which are being taken very seriously in the medical community. Fosamax is a main drug prescribed to address osteoporosis and pre-osteoporosis conditions. It strengthens weakened bones and prevents further bone loss. The benefits of this drug have been demonstrated to last at least 10 years.

Before patients lose the significant advantages of this therapy, the questions about possible problems need to be addressed.

What Is Fosamax?

Fosamax is a drug that is prescribed for the treatment of post-menopausal osteoporosis, for prevention of osteoporosis in post-menopausal women, as well as, for men at risk for osteoporosis, and in the treatment of Paget’s disease, a bone disease. It belongs to a class of drugs called bisphosphonates. Fosamax works by increasing bone mineral density. It slows resorption, which is the breakdown of normal bone remodeling. Fosamax is the oldest of the bisphosphonate drugs, has been used the most and studied the longest. The generic name for Fosamax is alendronate.

Fosamax Dosage

Daily and Weekly Dose Option. The dosage for treatment of osteoporosis in both men and women is 10 mg daily or 70 mg once a week. The dosage for prevention is 5 mg daily or 35 mg once a week. The drug is available in both pill and liquid form, with the dosage and the protocol the same for each.

There is an important procedure to follow when taking the drug to avoid possible negative interactions with foods or other medications. Instructions for taking the drug include taking the tablets with 6 to 8 ounces of water at least 30 minutes before taking any food, liquid, or medication of the day. Taking other liquids, including mineral water, foods, and medication, may interfere with absorption of the drug. The patient is directed to remain upright and to not lie down for at least 30 minutes after taking Fosamax and then only after some food has been taken. Because this protocol is the same for both, the daily and weekly doses, many patients prefer the weekly option.

Long-Term Potential

The optimal length of time the drug can be taken has not yet been determined. The drug has been demonstrated to be effective at continuing to improve bone density for a period of at least 10 years. It is not known whether longer treatment remains effective, or if it may actually cause some of the possible side effects. It is recommended that for patients at low risk of fracture, physicians consider discontinuing use of the drug after a 3 to 5 year period. Continuing evaluation of the risk potential for fracture should occur after discontinuing the drug.

Some doctors place their patients on a break after a number of years on the drug. Bisphosphonates are known to remain in the bones for a long time after the drugs are stopped, so studies are being done to determine the real impact of discontinuing the therapy.

While most patients tolerate Fosamax well, stomach ulcer and irritation of the esophagus are common side effects and other serious and even life threatening side effects have been identified.

Dangers Associated with Fosamax

Several possible serious side effects of Fosamax include: stomach ulcer, atrial fibrillation, osteonecrosis, esophageal cancer, hypocalcemia or low blood calcium levels, non-trauma induced fractures of the femur or thighbone, and severe musculoskeletal pain. The FDA has required the Fosamax label to include warnings of the possibility of osteonecrosis of the jaw, hypocalcemia, atrial fibrillation and severe musculoskeletal pain. The FDA evaluated the potential risk of esophageal cancer and determined that there was no evidence that Fosamax was a cause. However, there are competing studies that continue to suggest a link. More study is needed to fully assess the dangers.


Osteonecrosis, also known as Dead Jaw Syndrome, has been linked to the bisphosphonates. This very serious condition results in the complete collapse of the jaw bone which has become brittle from lack of block flow. Although this condition has been rare in Fosamax patients, the FDA has required a warning about Fosamax as a possible cause.


Fosamax has been identified as a possible cause of hypocalcemia, a condition of lower than normal levels of calcium in the blood, and it may increase the severity of symptoms in patients who already suffer from this condition. Symptoms of hypocalcemia include: muscle twitches, spasms, and cramps as well as tingling and numbness around the mouth or in fingers or toes.

Atrial Fibrillation

The evidence about possible heart rhythm problems in patients taking bisphosphonates for osteoporosis is conflicting, but serious enough to warrant a warning on the drug.

Esophageal Cancer

The FDA issued a Drug Safety Communication in 2011 about the potential risks of bisphosphonates causing esophageal cancer. The announcement noted that there was conflicting evidence as to whether or not Fosamax and other bisphosphonates cause cancer of the esophagus. One major study indicated no risk, while another study, examining patients who took bisphosphonates for more than three years, found that they exhibited double the risk of developing this cancer.

Severe Musculoskeletal Pain

The FDA has issued a warning about Fosamax, and several other bisphosphonates, regarding severe bone, muscle, and joint pain experienced by patients undergoing treatment with the drugs. The pain, in some cases, was very debilitating. In some cases, the pain stopped when the drug was discontinued and in other cases, it persisted even after discontinuing the drug therapy.

Fractures of the Femur

Evidence of a possible correlation between Fosamax and fractures across the thigh or femur was first presented in Singapore in 2005. Based on these findings, researchers at New York Hospital for Special Surgery, studied a group of patients who experienced this kind of fracture and found that a high enough percentage had been taking Fosamax to warrant caution and further study.

Publication of these initial findings led to anecdotal reports, both in support of the connection, between Fosamax and non-traumatic femur fractures and arguing against the connection. The follow up suggested that some correlation is likely. One concern, is that over time, the effect of the drug may change from slowing bone resorption and increasing bone density, to actually slowing new bone growth and reducing the bone’s ability to repair the tiny cracks that occur normally in bones. No studies have produced empirical evidence that the action of the drug, over time, may actually lead to fractures, but there is sufficient evidence that this is a possibility to take the prospect seriously.

Merck, the manufacturer of Fosamax, has committed to studying the effect of the drug on bone and, with the FDA, is monitoring adverse conditions that occur to identify cause and effect.


woman taking a pill

Image via Pexels

In the over 20 years it has been on the market Fosamax has produced very positive results in preventing fractures and, in doing so, preventing the deaths and disabilities those fractures would have caused. The possible side effects are serious and not to be taken lightly. Most experts believe that when Fosamax is taken appropriately, its benefits do greatly outweigh the risks and they advise against discontinuing Fosamax therapy for patients with severe cases of osteoporosis.

Some physicians have their patients take a break from the drug. This is especially common for the cases where the drug is taken to prevent the development of osteoporosis. The value of this approach has not yet been determined. This is another indication of the complexity of the issues involved in evaluating the possibility of side effects.

There definitely is a need for continued study of the effects of Fosamax and other bisphophonates. Controversies exist regarding the conclusions drawn from the studies of every side effect. While relationships exist, it isn’t clear whether the drugs cause the side effects or whether they are related to the underlying disease itself. These questions are very difficult because there is a strong desire to keep this powerful and effective drug available for patients if the risks are not greater than the rewards.

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